Real-time nonlinear adaptive force tracking control strategy for electrohydraulic systems with suppression of external vibration disturbance

Abstract

Electrohydraulic system (EHS) is extensively utilized in experimental testing field for exerting forces on specimen, and in many occasions, force tracking of EHS is confronted with external motion disturbance, which seriously deteriorates the force tracking performance. To address this problem, a real-time nonlinear adaptive force control strategy is developed in this paper. On the basis of the established nonlinear model for EHS, the proposed nonlinear adaptive force controller is obtained by a recursive backstepping method, where both servo-valve nonlinearity and parametric uncertainties of general electrohydraulic systems are accounted for during the controller design procedure. The first advantage for the proposed controller lies in the fact that the actuator's vibration disturbance information is utilized to serve the purpose of accurate force tracking. Besides, parametric uncertainties are effectively handled by the developed online adaptive updating law to achieve a higher force replication performance. Moreover, rigorous Lyapunov stability of the proposed controller is guaranteed. Finally, comparative experiments are implemented on a uniaxial EHS through xPC/Target rapid prototyping technique, and the relevant results validate the feasibility of the developed controller.

Recent Progress on Control Techniques of Shaking Table and Array Systems in China: An Overview

“…The experimental results show that this method solves the problem of traditional adaptive control sensitive to the initial value of parameters, overcomes the effects of nonlinearity and parameter uncertainty, and improves the transient response performance of the system. In [66] the nonlinear adaptive controller using the inverse method is designed to deal with the nonlinearity of the servo valve and the parameter uncertainty of the control algorithm. At the same time, the xPC/Target rapid prototyping technology was used on the single-axis shaking table.…”

Adaptive Super-twisting Sliding Mode Control of Hydraulic Servo Actuator with nonlinear features and modeling uncertainties

“…Hydraulic servo actuator is widely employed in modern industrial, such as heavy vehicle [1] and [2], load simulator [3], hot-pressing equipment [4], hydraulic manipulator [5], due to the virtues of small size-to-power ratio, high control precision, fast response performance and strong bearing capacity [6] to [8]. However, the nonlinear features and modeling uncertainties of hydraulic servo actuator complicates the dynamic model and hinders position tracking performance.…”

Integral Nonsingular Terminal Sliding Mode Control of Hydraulic Servo Actuator Based on Extended State Observer

“…e parametric uncertainties are mainly from unknown oil viscous damping [12], variable load stiffness [13], effective bulk modulus of fluid volumes [14], dead zone nonlinearity of valve [15], and oil temperature variations [16] while the model disturbance is mainly from uncertain external disturbance and unmodeled nonlinearities. Although traditional linear feedback control method based on the local linearization can obtain the modeling of hydraulic servo actuator, it does not consider the effect of nonlinear parameter behaviors and model disturbance [17].…”